It's amazing what we can do with software these days. We can write books, make beautiful artwork and build sophisticated mathematical models. Remember what life was like before Microsoft Office came along? Many of today's 20-somethings probably don't - a world without productivity software was never a world at all.

Unfortunately, with computer productivity, there's always a tradeoff. These days, state-of-the-art software is expensive, running into hundreds - or even thousands - of dollars per program.

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Luckily, there's another option - open source software. The open source movement emerged in the '90s when web developers joined forces to build free and public-use software. Under an open source license, a program's code is available for free distribution, adaptation and modification. Plus, you can use these programs

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commercially. Check out some of the free alternatives to the software you may be using.

1. Open Office
Most people are familiar with Microsoft programs like Excel, Word, Outlook and PowerPoint. Unfortunately, this software comes with an expensive price tag of more than $100. Consider Open Office as an alternative for your spreadsheets, word processing documents, presentations and basic graphics. There is even a database program for individuals and businesses who are working with data.

GIMP stands for GNU Image Manipulation Program, and you can use it to do just that - create and edit graphics. Especially if you're a casual user, this program provides enough resources to complete a variety of projects and serves as a reasonable stand-in for pricey programs like Photoshop - whether you're editing photographs or designing brochures.

3. Ubuntu
If you need a new operating system, Ubuntu is a user-friendly option. This Linux-based operating system can be installed on your hard drive, and it can also boot up off a CD on a per-use basis. If you're thinking about upgrading your Windows operating system, you might want to consider this free option. Do keep in mind, however, that advanced functions - like installing certain software or hardware devices - requires some technical aptitude.

Are you a student or professional statistician? Do you find yourself fighting over access to lab computers so that you can examine your datasets? Do you want to analyze data but can't afford sophisticated statistical packages? If this sounds like you, consider PSPP. This free program runs a number of statistical analyses (like t-tests and linear regression models) and can even generate graphs. It's a great alternative to SPSS - it even reads SPSS files. Plus, you can recommend your ideas for new features to the program's developers.

5. Freemind
Find yourself brainstorming and don't want to pay money to draft your plans? Check out Freemind, a program that helps you diagram concepts, plan, and examine relationships.

6. GNU Cash
This free accounting software is ideal for individuals and small businesses who need a finance management tool. It can be used to manage stocks, bonds, mutual fund accounts, invoices, jobs and more. If you like QuickBooks, you might want to give this open-source competitor a try.

The Bottom Line
Worried about usability? Over the last decade, open source software has become extremely user friendly and is available for Windows and Mac operating systems. There is no need to deal with complicated command line - all features are point and click in a convenient graphical environment.

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